That particular commercial location in every town where virtually no stores seem to be able to thrive. To be a true retail black hole, the location has to be highly visible, thus invalidating the location as the cause of the high mortality rate. In other words, the crumbling strip mall behind the industrial park doesn't count.
A Seinfeld episode was focused on the restaurant black hole (even if it wasn't called that on the show), the one spot in town where nobody can keep a restaurant open for more than a couple of months. The retail black hole implies a larger chunk of land.
My town's retail black hole, which is right on the major road leading through the center of town, has seen the deaths of the following, among others:
What makes it worse is that there's a Safeway, a Best Buy, a Kmart, and a Bennigan's in this shopping center. It's not as if nobody goes there, and it is on the main drag, so it's hardly out of the way.
There's got to be something behind it.